1145399809 has 4 divisors (see below), whose sum is σ = 1145638980. Its totient is φ = 1145160640.

The previous prime is 1145399791. The next prime is 1145399831. The reversal of 1145399809 is 9089935411.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1045099584 + 100300225 = 32328^2 + 10015^2 .

It is a cyclic number.

It is not a de Polignac number, because 1145399809 - 2⁷ = 1145399681 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1145399869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112252 + ... + 122029.

It is an arithmetic number, because the mean of its divisors is an integer number (286409745).

Almost surely, 2^1145399809 is an apocalyptic number.

It is an amenable number.

1145399809 is a deficient number, since it is larger than the sum of its proper divisors (239171).

1145399809 is an equidigital number, since it uses as much as digits as its factorization.

1145399809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239170.

The product of its (nonzero) digits is 349920, while the sum is 49.

The square root of 1145399809 is about 33843.7558347179. The cubic root of 1145399809 is about 1046.2907089004.

The spelling of 1145399809 in words is "one billion, one hundred forty-five million, three hundred ninety-nine thousand, eight hundred nine".